SAN BERNADINO, Calif. (AP)  California police say they have arrested a 46-year-old woman and are investigating her role in the death of her 5-year old son.

The Press Enterprise reports (http://bit.ly/1OPBZ9m ) that the boy died in his San Bernardino home Tuesday afternoon. Sgt. Emil Kokesh said in a statement that the boy’s injuries appeared to be caused by a sharp instrument.

Kokesh said the mother also had non-life-threatening injuries that seemed to be self-inflicted.

Police say they don’t believe anyone else was home at the time of the violence.

The news comes less than a week after 14 people were killed in the same city.